<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
            .bw{
                width: 2000px;
                height: 1000px;
                background-color: green;
                background-image: url(images/1.png);
                background-repeat: no-repeat;
                /* 设置背景图片的位置 */
                /* background-position: right top; */
                /* background-position: left bottom; */
                /* 如果只指定一个值，另外一个默认值就是居中对齐 */
                /* background-position: top; */
                /* background-position: 20px 20px; */
                /* background-position: 20px center; */
                background-position: center 20px;
            }
         </style>
     </head>
     <body>
         <div class="bw">

         </div>
     </body>
</html>